In vivo pharmacokinetics, biodistribution and anti-tumor effect of paclitaxel-loaded targeted chitosan-based polymeric micelle

Figures & data

Table 1. The physicochemical characterization of PTX-loaded polymeric micelles (n = 3).

Formulations	Particle size	Zeta potential	PDI	DL (%)	EE (%)
PTX/TS-CS	181.4 ± 7.5^a	23.2 ± 1.5	0.33 ± 0.05	22.6 ± 1.9^a	63.2 ± 6.8^a
PTX/TS-CS-PEG-FA	221.2 ± 12.5	20.2 ± 0.84	0.27 ± 0.07	28.2 ± 2.1	82.5 ± 7.3

PDI, polydispersity index.

^ap < 0.05.

Figure 1. XRD spectra of (a) PTX, (b) TS-CS-PEG-FA, (c) physical mixture of PTX and TS-CS-PEG-FA and (d) PTX-loaded TS-CS-PEG-FA.

Figure 2. DSC spectra of (a) PTX, (b) TS-CS-PEG-FA, (c) physical mixture of PTX and TS-CS-PEG-FA and (d) PTX-loaded TS-CS-PEG-FA.

Figure 3. Fluorescence image after the cells were incubated with fluorescent (a) TS-CS micelles and (b) TSCS.

Figure 4. The cellular uptake percentage of FITC/CS-TS and FITC/TS-CS-PEG-FA micelles in 4T1 cells (the polymer concentrations were 20 μg/ml).

Figure 5. In vitro cytotoxicity of various PTX formulations and blank micelles against 4T1 cell line after 72 h incubation. Data were plotted as the mean ± SD of three measurements.

Figure 6. Effect of free folic acid on viability of 4T1 cells incubated with PTX/TS-CS-PEG-FA micelles at PTX concentration of 1.17 μM.

Figure 7. Tumor volume change in mice with PTX/TS-CS, PTX/TS-CS-PEG-FA, Anzatax®, blank micelles or saline (n = 6) (a) images of whole mice were taken at 25 days after tumor inoculation (b).

Figure 8. H&E-stained tumor slices from mice on the 25nd day after treatment with (a) saline, (b) Anzatax®, (c) PTX/TS-CS and (d) PTX/TS-CS-PEG-FA. Images were obtained under Olympus IX71 optical microscope.

Table 2. In vivo anti-tumor effect of PTX formulations against 4T1 tumor in Balb/c mice (n = 6).

	Body weight (g)
Drug	Initial	Final	Tumor weight (g)	TIR (%)
Saline	23.42 ± 0.76	28.45 ± 1.25	1.09 ± 0.38	–
Balnk TS-CS-PEG-FA	24.53 ± 1.17	29.38 ± 1.07	1.01 ± 0.24	7.89
Anzatax®	25.95 ± 1.01	21.86 ± 1.82	0.51 ± 0.17	45.6
PTX/TS-CS	25.59 ± 0.96	28.04 ± 0.89	0.39 ± 0.12	55.2
PTX/TS-CS-PEG-FA	26.17 ± 0.84	27.56 ± 1.43	0.15 ± 0.0.5	85.6

Figure 9. Mean concentration–time profile of PTX in Balb/c mice plasma after i.v. administration of Anzatax® and PTX/TS-CS-PEG-FA. Each point represents the mean ± SD (n = 3).

Figure 10. The PTX concentration in mice receiving Anzatax® or PTX/TS-CS-PEG-FA in tissues at different time points (0.083, 0.5, 1, 2, 4, 8 and 12 h) (mean ± SD, n = 5).

Table 3. Pharmacokinetic parameters of PTX in the two formulations after i.v. administration.

Parameters	Anzatax®	PTX/TS-CS-PEG-FA
Vd (L/kg)	2.704 ± 0.417	5.603 ± 0.914^a
T1/2α (h)	0.238 ± 0.103	0.342 ± 0.057
T1/2ß (h)	2.486 ± 0.231	4.641 ± 0.384^a
CL (ml/h/kg)	727.5 ± 51.66	832.97 ± 76.27
AUC (0-∞) (µg h/ml)	13.36 ± 1.129	11.81 ± 1.402
MRT (0-∞) (h)	2.751 ± 0.143	4.931 ± 0.426^a

Data represent mean ± SD (n = 3). V_d, apparent volume of distribution; T_1/2α, apparent plasma half-life of distribution phase; T_1/2ß, apparent plasma half-life of elimination phase; CL, total body clearance; AUC_0–∞, the area under the plasma concentration–time curve from time zero to time infinity; MRT_0–∞, mean residence time from time zero to time infinity.

^ap < 0.01 compared with Anzatax®.

Table 4. AUC and MRT of PTX in tissue after i.v. administration of 10 mg/kg dose of Anzatax® and PTX/TS-CS-PEG-FA micelles.

	AUC (0–tn)^a (µgh/ml or µgh/g)			MRT^b (0–tn) (h)
Tissues	Anzatax®	PTX/TS-CS- PEG-FA	Re	Anzatax®	PTX-CS-TS- PEG-FA
Plasma	12.66	10.48	0.83	2.61	3.15
Heart	60.48	41.39	0.68	3.44	4.62
Kidney	94.70	127.1	1.34	3.46	3.62
Lung	72.90	58.62	0.80	2.90	2.79
Spleen	64.67	36.22	0.56	4.36	3.11
Liver	175.3	146.19	0.84	3.75	3.19
Tumor	407.1	732.4	1.81	5.13	5.28

Re, ratio of AUC (PTX micelles)/AUC (Anzatax®).

^aThe area under the plasma concentration–time curve from time zero to the last time point examined.

^bThe mean residence time from time zero to the last time point.